U.S. patent application number 16/723072 was filed with the patent office on 2020-07-09 for modular spine stabilization system and associated instruments.
The applicant listed for this patent is Paradigm Spine, LLC. Invention is credited to Rudolph Bertagnoli, Stephan ECKHOF, Markus Salvermoser, William R. Sears.
Application Number | 20200214743 16/723072 |
Document ID | / |
Family ID | 71101941 |
Filed Date | 2020-07-09 |
![](/patent/app/20200214743/US20200214743A1-20200709-D00000.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00001.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00002.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00003.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00004.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00005.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00006.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00007.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00008.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00009.png)
![](/patent/app/20200214743/US20200214743A1-20200709-D00010.png)
View All Diagrams
United States Patent
Application |
20200214743 |
Kind Code |
A1 |
ECKHOF; Stephan ; et
al. |
July 9, 2020 |
MODULAR SPINE STABILIZATION SYSTEM AND ASSOCIATED INSTRUMENTS
Abstract
An implantable, modular spine stabilization system that allows
for multi-level treatment of the spine by providing either rigid
fixation or dynamic stabilization at different levels to be treated
is provided. This modular spine stabilization system may be
configured to span multiple spine levels, and have a curvature that
closely matches the curvature of the spine over those multiple
levels to be treated. Further, the modular spine stabilization
system allows adjustment of the curvature of the overall system
such that the system may be adapted for a patient for a customized
fit. Instruments are also provided for the assembly and/or
implantation of the modular spine stabilization system. The
associated instruments may include instruments for adjusting the
curvature of the system to the patient, and for implanting the
curved system into the patient. The instruments may be configured
for implantation of the system in a minimally invasive surgery.
Inventors: |
ECKHOF; Stephan;
(Rietheim-Weilheim, DE) ; Salvermoser; Markus;
(Tuttlingen-Mohringen, DE) ; Bertagnoli; Rudolph;
(Vienna, AT) ; Sears; William R.; (Warrawee,
AU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Paradigm Spine, LLC |
New York |
NY |
US |
|
|
Family ID: |
71101941 |
Appl. No.: |
16/723072 |
Filed: |
December 20, 2019 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62783700 |
Dec 21, 2018 |
|
|
|
62783541 |
Dec 21, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 2090/061 20160201;
A61B 17/7028 20130101; A61B 17/8863 20130101; A61B 17/7032
20130101; A61B 90/92 20160201; A61B 17/863 20130101; A61B 17/7004
20130101; A61B 17/7014 20130101; A61B 17/7026 20130101; A61B
17/7083 20130101; A61B 17/7085 20130101 |
International
Class: |
A61B 17/70 20060101
A61B017/70 |
Claims
1. A kit for modular spine stabilization, comprising: an
implantable modular spine stabilization system comprising: one or
more flexible couplers for dynamic stabilization of a spinal
segment of a patient's spine, each flexible coupler having a stem;
one or more rigid rods for rigid stabilization of a spinal segment
of the patient's spine, each rigid rod having an elongated shaft;
and one or more bone fasteners for attaching the one or more
flexible couplers or rigid rods to the patient's spine; and an
instrument set for use with the implantable modular spine
stabilization system, the instrument set including a bending
instrument for bending a stem of one of the flexible couplers.
2. The kit of claim 1, wherein the one or more flexible couplers
are configured to attach to each other.
3. The kit of claim 1, wherein the one or more flexible couplers
are configured to attach to one of the rigid rods.
4. The kit of claim 1, wherein the stem of the one or more flexible
couplers is bendable.
5. The kit of claim 1, wherein the stem of the one or more flexible
couplers is either curved or straight.
6. The kit of claim 1, wherein the stem of the one or more flexible
coupler has a threaded end.
7. The kit of claim 1, wherein the one or more flexible couplers
comprises a body having a threaded opening.
8. The kit of claim 1, wherein the elongated shaft of the one or
more rigid rods is either curved or straight.
9. The kit of claim 1, wherein the elongated shaft of the one or
more rigid rods has a threaded end.
10. The kit of claim 1, wherein the one or more flexible couplers
are differently sized.
11. The kit of claim 1, wherein the one or more rigid rods are
differently sized.
12. The kit of claim 1, wherein the bending instrument comprises a
base having a pivoting arm, a pivoting rod holder, and a radius of
curvature selection wheel, the pivoting arm having a pusher bar and
pusher head extending from a lower surface therefrom, and the
pivoting rod holder having a portal for receiving a rod of a
medical device to be bent, wherein the lowering of the pivoting arm
causes the pusher bar to press against the radius of curvature
selection wheel and the pusher head to press against the rod held
within the pivoting rod holder.
13. The kit of claim 12, wherein the pivoting arm includes a handle
attachment end.
14. The kit of claim 12, wherein the base includes a handle
attachment end.
15. The kit of claim 12, wherein the radius of curvature selection
wheel includes one or more detents corresponding to a different
radius of curvature.
16. The kit of claim 12, wherein the pivoting arm attaches to the
base at a pivoting hinge.
17. The kit of claim 12, wherein the pivoting rod holder includes a
portal for receiving the stem of the flexible coupler.
18. The kit of claim 12, wherein the portal is threaded.
19. The kit of claim 12, further including a damper between the
pivoting arm and the base.
20. The kit of claim 12, further including detachable handles for
attachment to the base and arm.
21-60. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/783,700, filed Dec. 21, 2018 and U.S.
Provisional Application No. 62/783,541, filed Dec. 21, 2018, the
entire contents of which are herein incorporated in their entirety
by reference.
FIELD
[0002] The present disclosure generally relates to medical devices
for the treatment of spinal conditions, and specifically to an
implantable, modular spine stabilization system for controlling or
restricting relative motion between vertebrae Instruments for the
assembly and/or implantation of such a modular spine stabilization
system are also provided.
BACKGROUND
[0003] The spine includes a series of joints known as motion
segment units. Each unit represents the smallest component of the
spine to exhibit a kinematic behavior characteristic of the entire
spine. The motion segment unit is capable of flexion, extension,
lateral bending, and translation. The components of each motion
segment unit include two adjacent vertebrae, the corresponding
apophyseal joints, an intervertebral disc, and connecting
ligamentous tissue, with each component of the motion segment unit
contributing to the mechanical stability of the joint. For example,
the intervertebral discs that separate adjacent vertebrae provide
stiffness that helps to restrain relative motion of the vertebrae
in flexion, extension, axial rotation, and lateral bending.
[0004] When the components of a motion segment unit move out of
position or become damaged due to trauma, mechanical injury or
disease, severe pain and further destabilizing injury to other
components of the spine may result. In a patient with degenerative
disc disease (DDD), a damaged disc may provide inadequate
stiffness, which may result in excessive relative vertebral motion
when the spine is under a given load, causing pain and further
damage to the disc. Depending upon the severity of the structural
changes that occur, treatment may include fusion, discectomy,
and/or a laminectomy.
[0005] Known treatments for spinal instability can include
long-term medical management or surgery. Medical management is
generally directed at controlling the symptoms, such as pain
reduction, rather than correcting the underlying problem. For some
patients, this may require chronic use of pain medications, which
may alter the patient's mental state or cause other negative side
effects. Surgical treatment typically includes decompression
procedures to restore normal disc height, realign the column, and
alleviate the pain.
[0006] Current surgical treatments often involve the immobilization
or fusion of unstable motion segment units, sometimes with the
removal of adjacent tissue. One such treatment method involves the
rigid fixation of the spine at one or more levels by securing a
rigid rod against the spine to prevent motion and thereby enable
fusion.
[0007] An alternative surgical treatment also stabilizes the spine,
but preserves motion instead of promoting fusion. This type of
dynamic stabilization typically involves the fixation of a dynamic
or spring-like coupler between vertebrae, which would still serve
to stabilize and limit motion of the spine, but also allow
close-to-normal motion, mimicking the physiological response of a
healthy motion segment and providing pain relief, at that
level.
[0008] There is, nevertheless, a need for a surgical treatment that
can address multi-level spine stabilization, and an implantable,
modular spine stabilization system that can achieve one or the
other type of stabilization at different levels. Rather than having
different or separate rod systems to treat multiple levels of the
same spine by either rigidly fixing or dynamically stabilizing a
single level, what would be desirable is a modular spine
stabilization system that could allow either rigid fixation or
dynamic stabilization at each level of the same spine to be
treated. Further, since this spine stabilization system would span
multiple spine levels, it would be further desirable to enable the
system to have a curvature that closely matches the curvature of
the spine over those multiple levels to be treated, and even more
desirable to be able to adjust the curvature of the system to the
patient for a customized fit. Accordingly, associated instruments
for the assembly and/or implantation of such a modular spine
stabilization system are also desirable.
SUMMARY
[0009] The present disclosure provides an implantable, modular
spine stabilization system that allows for multi-level treatment of
the spine by providing either rigid fixation or dynamic
stabilization at different levels to be treated. This modular spine
stabilization system may be configured to span multiple spine
levels, and have a curvature that closely matches the curvature of
the spine over those multiple levels to be treated. Further, the
modular spine stabilization system allows adjustment of the
curvature of the overall system such that the system may be adapted
for a patient for a customized fit.
[0010] Instruments are also provided for the assembly and/or
implantation of the modular spine stabilization system. The
associated instruments may include instruments for adjusting the
curvature of the system to the patient, and for implanting the
curved system into the patient. The instruments may be configured
for implantation of the system in a minimally invasive surgery.
Methods for stabilizing a spine using the implantable, modular
spine stabilization system and the associated instruments for
assembly and implantation are also provided.
[0011] In one exemplary embodiment, a kit for modular spine
stabilization is provided. The kit may comprise an implantable
modular spine stabilization system and an associated instrument set
for use with the implantable modular spine stabilization system.
The spine stabilization system may comprise one or more flexible
couplers for dynamic stabilization of a spinal segment of a
patient's spine. Each coupler may have a stem. The system may
further comprise one or more rigid rods for rigid stabilization of
a spinal segment of the patient's spine. Each rigid rod may have an
elongated shaft. One or more bone fasteners for attaching the
flexible couplers or rigid rods to a patient's spine are also
provided in the system.
[0012] An instrument set for attaching the spine stabilization
system to the patient's spine may also be provided with the kit.
The instrument set may include a bending instrument for bending a
stem of one of the flexible couplers.
[0013] In some embodiments, a flexible coupler may be configured to
attach to one or more flexible couplers. In other embodiments, a
flexible coupler may be configured to attach to a rigid rod.
[0014] The stem of the flexible coupler may be curved, or the stem
may be straight. Likewise, the shaft of the rigid rod may be
curved, or it may be straight. The stem of the flexible coupler may
be bendable. The stem and shaft of the flexible coupler and rigid
rod, respectively, have threaded ends while the flexible coupler
comprises a body having a threaded opening, so that these
components can be threadedly connected in series to one
another.
[0015] The one or more flexible couplers may be provided as a set,
and may be differently sized. Likewise, the rigid rods may be
provided as a set, and may be differently sized.
[0016] In one exemplary embodiment, the bending instrument may
comprise a base having a pivoting arm, a pivoting rod holder, and a
radius of curvature selection wheel. The pivoting arm may have a
pusher bar and a pusher head extending from a lower surface
therefrom. The pivoting rod holder may have a portal for receiving
a rod of a medical device to be bent. The bending instrument may be
configured such that the lowering of the pivoting arm causes the
pusher bar to press against the radius of curvature selection wheel
and the pusher head to press against the rod held within the
pivoting rod holder.
[0017] The pivoting arm can include a handle attachment end.
Likewise, the base can also include a handle attachment end. The
radius of curvature selection wheel includes one or more detents
corresponding to a different radius of curvature. In addition, the
pivoting arm can attach to the base at a pivoting hinge.
[0018] The pivoting rod holder can include a portal, which may be
threaded, for receiving the rod of the medical device. The bending
instrument may also include a damper between the pivoting arm and
the base. The bending instrument may also include detachable
handles for attachment to the base and arm.
[0019] As previously mentioned, the bending instrument may be used
for bending rods of medical devices. In particular, the bending
instrument may be used to bend a stem of the medical device. The
medical device may be a flexible coupler such as the one provided
in the modular spine stabilization system of the present
disclosure.
[0020] Other instruments provided with the instrument set of the
present disclosure may include a flexible coupler and rod inserter
tool. The flexible coupler and rod inserter tool may include an
angularly adjustable neck, and be configured for use in a minimally
invasive surgery.
[0021] Another instrument that may be provided with the instrument
set of the present disclosure includes a contouring template. Still
another instrument may include a flexible coupler and rigid rod
clamping instrument configured to clamp onto a guide rod, which may
also be provided with the instrument set of the present
disclosure.
[0022] The modular spine stabilization system of the present
disclosure may include bone fasteners. The bone fastener may
comprise a head portion and a shank portion. The head portion may
include a cavity for receiving an implantable device. The shank
portion may include an elongated shaft extending to a distal tip.
The shank portion may have an enlarged head captured within the
cavity of the head portion and being defined by a first leading
threaded portion adjacent the distal tip. The shank portion may be
defined by a first leading threaded portion adjacent the distal
tip, a second trailing threaded portion adjacent the head portion,
and an intermediate threaded portion extending between the first
and second threaded portions. In one exemplary embodiment, the
implantable device may comprise a rod.
[0023] In one embodiment, the first leading threaded portion
includes quad lead threads and the second trailing threaded portion
may include quad lead threads. In some embodiments, the shank
portion may have a generally uniform diameter from the second
trailing threaded portion to the end of the intermediate threaded
portion, while the first leading threaded portion may have a
conical shape. In some embodiments, the first leading threaded
portion may include cutting notches. The bone fastener may be
cannulated and include cement holes for use with bone cement, in
some embodiments.
[0024] Additionally, the bone fastener may be color coded for
different sizes, and may be configured with a self-tapping distal
tip. A locking device for securing the implantable device within
the cavity may be provided, in which the locking device is a set
screw. Further, the head portion may be attached to an extended
head portion at a scored region. This extended head portion may be
configured to break away from the head region after use.
Additionally, the bone fastener may include an elongate head region
for use in a minimally invasive surgery. Once the assembly process
is completed, this elongate head region may be snapped off.
[0025] The present disclosure may also provide an implantable,
modular spine stabilization system. This system may include one or
more flexible couplers for dynamic stabilization of a spinal
segment of a patient's spine. Each flexible coupler may have a
flexible main body and a bendable stem extending therefrom. The
system may also include one or more rigid rods for rigid
stabilization of a spinal segment of the patient's spine. Each
rigid rod may have an elongated shaft.
[0026] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory only and are not restrictive of the disclosure.
Additional features of the disclosure will be set forth in part in
the description which follows or may be learned by practice of the
disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate several
embodiments of the disclosure and together with the description,
serve to explain the principles of the disclosure.
[0028] FIG. 1 is a perspective view of an exemplary embodiment of a
modular spine stabilization system of the present disclosure.
[0029] FIG. 2A is a perspective view of an exemplary embodiment of
a flexible coupler of the present disclosure having a curved
stem.
[0030] FIG. 2B is a perspective view of an exemplary embodiment of
a flexible coupler of the present disclosure having a straight
stem.
[0031] FIG. 2C is a partial cutaway view of the flexible coupler of
FIG. 2B showing an internal range-of-motion limiting mechanism.
[0032] FIG. 3A is a perspective view of an exemplary embodiment of
a rigid rod of the present disclosure having a curved shaft.
[0033] FIG. 3B is a perspective view of an exemplary embodiment of
a rigid rod of the present disclosure having a straight shaft.
[0034] FIGS. 4A to 4F illustrate various configurations of the
modular spine stabilization system of the present disclosure, in
which:
[0035] FIG. 4A is an exploded view of a system configuration
comprising a flexible coupler with a straight stem and a curved
rod;
[0036] FIG. 4B is a perspective view of a system configuration
comprising a flexible coupler with a curved stem attached to a
curved rod;
[0037] FIG. 4C is a perspective view of a system configuration
comprising a flexible coupler with a straight stem attached to a
straight rod;
[0038] FIG. 4D is a perspective view of a system configuration
comprising a flexible coupler with a curved stem attached to a
curved rod;
[0039] FIG. 4E is perspective view of a system configuration
comprising two flexible couplers and a rod, and all of which have
curved stems or shafts, for attachment in series together; and
[0040] FIG. 4F is a perspective view of a system configuration
comprising two flexible couplers and a rod, all of which have
straight stems or shafts.
[0041] FIG. 5 shows exemplary embodiments of instruments of an
instrument set of the present disclosure which are useful for
contouring a stem of a flexible coupler.
[0042] FIG. 6 shows an exemplary method of using some of the
instruments of FIG. 5 for determining a curvature of a flexible
coupler.
[0043] FIG. 7A is a perspective view of an exemplary embodiment of
a bending instrument of the present disclosure for bending a stem
of a flexible coupler, attached to detachable handles.
[0044] FIG. 7B is a perspective view of the bending instrument of
FIG. 7A, without the detachable handles.
[0045] FIGS. 8A to 8H illustrate a method for bending a stem of a
flexible coupler using the bending instrument of FIGS. 7A and 7B,
in which:
[0046] FIG. 8A shows the bending instrument in an open position
with the arm raised;
[0047] FIG. 8B shows the flexible coupler mounting unit swiveled
upward on the bending instrument;
[0048] FIG. 8C shows the selected flexible coupler inserted into
the flexible coupler mounting unit of the bending instrument,
including an enlarged view;
[0049] FIG. 8D shows the flexible coupler mounting unit swiveled
back to reside within the base of the bending instrument and the
correct radius chosen, including an enlarged view;
[0050] FIG. 8E is a partial cutaway view of the bending instrument
in a partially closed position with the arm lowered.
[0051] FIG. 8F is a partial cutaway view of the bending instrument
in a fully closed position with the arm fully lowered;
[0052] FIG. 8G shows the bending instrument in an open position,
with the flexible coupler mounting unit swiveled upward, including
an enlarged view; and
[0053] FIG. 8H shows the flexible coupler with a bent stem being
removed from the bending instrument.
[0054] FIG. 9A is a front view of an exemplary embodiment of a bone
fastener of the present disclosure for use with the modular spine
stabilization system.
[0055] FIG. 9B illustrates a perspective view of the bone fastener
of FIG. 9A and having an attached extended head portion.
[0056] FIG. 9C illustrates a shaft for use with the head portion of
the bone fastener of FIG. 9A.
[0057] FIG. 9D illustrates a top-down view of the shaft of FIG. 9C,
in which the head region may include an extended tulip head.
[0058] FIGS. 10A and 10B illustrate a method of using the bone
fastener of FIGS. 9A to 9D to secure the modular spine
stabilization system of FIG. 1.
[0059] FIGS. 11A to 11C are perspective views of an exemplary
embodiment of a flexible coupler and rod inserter tool of the
present disclosure, in which:
[0060] FIG. 11A illustrates a perspective view of the inserter
tool;
[0061] FIG. 11B shows a method of using the inserter tool to grasp
a flexible coupler of the system of FIG. 1; and
[0062] FIG. 11C shows the inserter tool in use with a flexible
coupler of the system of FIG. 1.
[0063] FIGS. 12A to 12E illustrate an exemplary method of using the
inserter tool of FIGS. 11A to 11C, in which:
[0064] FIG. 12A illustrates an exemplary surgical guide for making
incisions to access the patient's spine; and
[0065] FIGS. 12C to 12E show a method of using the inserter tool to
introduce a flexible coupler and rod construct into the patient's
spine.
[0066] FIG. 13 is a perspective view of the modular spine
stabilization system of the present disclosure in use with a
crosslink.
[0067] FIG. 14A is a perspective view of an exemplary embodiment of
a measurement tool of the instrument set of the present disclosure,
for determining a crosslink length.
[0068] FIG. 14B shows the measurement tool of FIG. 14A in use to
measure a distance between two pairs of rods.
[0069] FIG. 15A is a perspective view of another exemplary
embodiment of a measurement tool of the instrument set of the
present disclosure, for measuring a length of a system
configuration.
[0070] FIG. 15B shows a partial cutaway view of the measurement
tool of FIG. 15A in use to measure a length of a system
configuration.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0071] This description and the accompanying drawings illustrate
exemplary embodiments and should not be taken as limiting, with the
claims defining the scope of the present disclosure, including
equivalents. Various mechanical, compositional, structural, and
operational changes may be made without departing from the scope of
this description and the claims, including equivalents. In some
instances, well-known structures and techniques have not been shown
or described in detail so as not to obscure the disclosure. Like
numbers in two or more figures represent the same or similar
elements. Furthermore, elements and their associated aspects that
are described in detail with reference to one embodiment may,
whenever practical, be included in other embodiments in which they
are not specifically shown or described. For example, if an element
is described in detail with reference to one embodiment and is not
described with reference to a second embodiment, the element may
nevertheless be claimed as included in the second embodiment.
Moreover, the depictions herein are for illustrative purposes only
and do not necessarily reflect the actual shape, size, or
dimensions of the system or illustrated components.
[0072] It is noted that, as used in this specification and the
appended claims, the singular forms "a," "an," and "the," and any
singular use of any word, include plural referents unless expressly
and unequivocally limited to one referent. As used herein, the term
"include" and its grammatical variants are intended to be
non-limiting, such that recitation of items in a list is not to the
exclusion of other like items that can be substituted or added to
the listed items.
[0073] The present disclosure provides an implantable, modular
spine stabilization system that allows for multi-level treatment of
the spine by providing either rigid fixation or dynamic
stabilization at different levels to be treated. This modular spine
stabilization system may be configured to span multiple spine
levels, and have a curvature that closely matches the curvature of
the spine over those multiple levels to be treated. Further, the
modular spine stabilization system allows adjustment of the
curvature of the overall system such that the system may be adapted
for a patient for a customized fit.
[0074] Instruments are also provided for the assembly and/or
implantation of the modular spine stabilization system. The
associated instruments may include instruments for adjusting the
curvature of the system to the patient, and for implanting the
curved system into the patient. The instruments may be configured
for implantation of the system in a minimally invasive surgery.
[0075] Turning now to the drawings, FIG. 1 illustrates an exemplary
embodiment of a modular spine stabilization system 100 of the
present disclosure. The system 100 may be configured for
multi-level treatment of the spine, with different, individual
levels being either rigidly fixed or dynamically stabilized. As
shown, a pair of implantable flexible couplers 120 may be connected
in series, along with an implantable rigid rod 140, to enable
multi-level spine stabilization with varied degrees of fixation at
individual levels. Bone fasteners 160 may be used to secure the
couplers 120 and the rigid rod 140 to the spine. These flexible
couplers 120 allow limited motion at that level where they are
positioned, while the rigid rod 140 provides rigid fixation where
it is connected.
[0076] The modular spine stabilization system 100 of the present
disclosure may provide two different types of flexible couplers for
dynamic stabilization of a spine level: FIG. 2A shows an exemplary
embodiment of a flexible coupler 120 having a curved or angled stem
132b, while FIG. 2B shows an exemplary embodiment of a flexible
coupler 120 having a straight stem 132a. Each of the stems 132a,
132b may include a threaded end 138, as shown. The flexible coupler
120 may be similar to the flexible coupler described in U.S. Pat.
No. 10,092,329, U.S. Pat. No. 9,522,018, and U.S. Pat. No.
8,920,473, the contents of all of which are herein incorporated in
their entirety by reference. Accordingly, as shown, the flexible
coupler 120 may comprise a main body 122 such as the cylindrical
body shown in FIGS. 2A to 2C. The flexible coupler body 122 may be
flexible, compressible, and/or extendable, and formed from a series
of coil units 122a. The series of coil units 122a may be connected
to one another to form a stepwise series of slots 124. Each slot
124 terminates at an opening 126 of the flexible body 122. A
threaded opening 128 may be provided on the flexible body 122, as
shown in FIG. 2C. If so desired, the flexible coupler body 122 may
comprise an internal distraction-compression stopping mechanism to
control or limit the range of motion that can be offered. For
example, as shown in FIG. 2C, a range-of-motion limiting mechanism
136 may be provided within the flexible coupler body 122. The
internal distraction-compression stopping mechanism 136 may be
similar to the one described in the aforementioned patents.
[0077] In some embodiments, the series of coil units 122A can be
formed from a single piece of material such that the units 122A are
integrally connected with one another. For example, in one
embodiment, the coil units 122A can be etched or cut from a single,
tubular piece of material. In other embodiments, one or more coil
units 122A can be formed individually and stacked upon one another.
The stacked coil units 122A can be connected to one another, for
example, by welding or through mechanical connections.
[0078] It is contemplated that the flexible coupler body 122 may
vary in degree of stiffness based on the height, width, distance or
angle between two adjacent slots 124 and the number of units 122A
forming the coupler body 122. Further, one or more units 122A may
be formed from different materials so as to vary the mechanical
properties of the body 122. In addition, the dimensions of the
units 122A, slots 124, and openings 126 can be varied within a
single body 122.
[0079] The modular spine stabilization system 100 of the present
disclosure may also provide two different types of rigid rods for
rigid fixation of a spine level: FIG. 3A shows a rigid rod 140
having a curved or angled shaft 142b, while FIG. 3B shows a rigid
rod 140 having a straight shaft 142a. Each of the shafts 142a, 142b
may have a tapered, blunt end 146 and an opposed, threaded end 148,
as shown.
[0080] It is understood that each of these flexible couplers 120 or
rigid fixation rods 140 may be provided in various sizes (e.g.,
length, diameter, angle of stem).
[0081] One of the advantages of the modular spine stabilization
system 100 of the present disclosure is that it is customizable,
and allows the user to selective choose which type of flexible
coupler 120 and/or which type of rigid rod 140 to attach in series
together, depending on the level of rigidity required at that
spinal level, as well as the curvature of the spine to be
stabilized. This modularity provides the surgeon with ultimate
flexibility in customizing the multi-level spine stabilization
system to the patient's needs. For example, FIGS. 4A to 4F show the
various modular constructs, or configurations, in which this
modular spine stabilization system 100 may be assembled and
utilized:
[0082] FIG. 4A shows a system configuration, or construct,
comprising a flexible coupler 120 with a straight stem 132a to be
attached to a rigid rod 140 having a curved shaft 142b, while FIG.
4B shows a system configuration, or construct, comprising a
flexible coupler 120 with a curved stem 132b attached to a rigid
rod 140 having a curved shaft 142b.
[0083] FIG. 4C shows a system configuration, or construct,
comprising a flexible coupler 120 with a straight stem 132a
attached to a rigid rod 140 with a straight shaft 142a, while FIG.
4D shows a system configuration, or construct, comprising a
flexible coupler 120 with a curved stem 132b attached to a rigid
rod 140 having a curved shaft 142b.
[0084] FIG. 4E shows a system configuration, or construct,
comprising two flexible couplers 120 and a rigid rod 140, all of
which have curved stems 132b or a curved shaft 142b, attached in
series together. FIG. 4F shows a system configuration, or
construct, comprising two flexible couplers 120 and a rigid rod
140, all of which have straight stems 132a or a straight shaft
142a, attached in series together. Of course, it is understood that
any one of those dynamic or rigid components could be substituted
with one having a straight stem or shaft as well. The various
combinations and configurations or constructs shown are merely for
illustration purposes only.
[0085] A set of instruments 200 may be provided for implanting the
modular spine stabilization system 100. The instruments may be
particularly useful fora minimally invasive surgery (MIS)
technique.
[0086] FIG. 5 shows various instruments forming part of the
instrument set 200 of the present disclosure that can be used to
contour (i.e., bend) the stem 132 of the flexible coupler 120 in
order to adapt it to the unique curvature of the patient's spine,
as shown in FIG. 6. The patient's spine 10 has a natural curvature
that poses a challenge when connecting components such as the
flexible couplers 120 of the present disclosure together in series,
in order to span and treat multiple levels. By creating a curved
stem 132b, the flexible couplers 120 are able to connect end-to-end
and mimic the curvature of that portion A of the patient's spine 10
to be treated, and where the flexible couplers 120 are to be
implanted. These instruments include a grasper tool 210 which
cooperates with a clamping instrument 220 that can hold onto a
guide rod 230. A flexible coupler template 240 may be provided
which may help the surgeon to approximate the correct angle of the
stem 132 (i.e., length and angle of curved stem) based on the size
of the flexible coupler 120. Using these tools, the surgeon may be
able to select the appropriately sized coupler and also determine
the correct contour for the stem 132 of the flexible coupler
120.
[0087] Another instrument that forms part of the instrument set 200
of the present disclosure is a bending instrument 250 for bending
the stem 132 of the flexible coupler 120. As shown in FIG. 7A, in
one exemplary embodiment, the bending instrument 250 may comprise a
base or main body 252 configured to attach to detachable handles
270. FIG. 7B illustrates the base 252 without the detachable
handles 270, and in greater detail. Within the bending instrument
base 252 resides a flexible coupler mounting unit 254. The flexible
coupler mounting unit 254 can be pivoted or raised to a
perpendicular, 90 degree angle relative to the base 252 after
lifting arm 256. This allows the straight stem 132a of the flexible
coupler 120 to be inserted into the mounting unit 254, as will be
described in greater detail below. The arm 256 attaches to the base
252 with a pivoting hinge mechanism 260. Once the arm 256 is
raised, placing the bending instrument 250 in an open position, the
flexible coupler mounting unit 254 can be pivoted 90 degrees upward
to receive the straight stem 132a of the flexible coupler 120. The
arm 256 may include a handle attachment end 266 for attachment to a
detachable handle 270. Similarly, the base 254 may also include a
handle attachment knob 268 for attachment to a detachable handle
270. Stability bars 278 extending from the base 252 may also be
provided, as shown in FIG. 7B.
[0088] FIGS. 8A to 8H illustrate the steps for bending the straight
stem 132a using the bending instrument 250 of FIGS. 7A and 7B. FIG.
8A shows the bending instrument 250 in an open position, i.e., the
arm 256 is raised upwards, allowing the flexible coupler mounting
unit 254 to swivel or flip upwards 90 degrees on the bending
instrument base 252, as shown in FIG. 8B. This pivoting of the
flexible coupler mounting unit 254 exposes a portal 266 for
receiving the straight stem 132a of the flexible coupler 120. Once
the portal 266 is exposed, the selected flexible coupler 120 may be
inserted by threading the threaded end 138 of the straight stem
132a into the portal 266 of the flexible coupler mounting unit 254
of the bending instrument 250, as shown in FIG. 8C.
[0089] Next, the desired radius of curvature for the straight stem
132a is selected by dialing the appropriate degree of bending on
the radius selection wheel 262. As previously discussed, the
desired radius of curvature may be selected using the template 240
provided as a selection guide. This radius selection wheel 262
includes various angled ramps or detents 264 about its
circumference. Rotation of the radius selection wheel 262 exposes a
particular angled ramp or detent 264, as represented in FIG. 8D, in
which the flexible coupler mounting unit 254 is pivoted back 90
degrees counterclockwise to lay within the base 252.
[0090] After the correct radius has been chosen and the radius
selection wheel 262 rotated to the correct position corresponding
to the chosen radius, the arm 256 of the bending instrument 250 may
then be lowered, as shown in FIG. 8E. In the process of lowering
the arm 256, a protruding pusher bar 274 extending from the arm 256
pushes against the radius selection wheel 262 at the selected
detent 264, as shown in FIGS. 8E and 8F. A pusher head 272
extending from the arm 256 urges against the straight stem 132a
with a corresponding amount of force, thus bending the straight
stem 132a of the flexible coupler 120. The pusher head 272 may have
at a free end a contoured or curved contact surface 274 to allow it
to effectively push against the cylindrical outer surface of the
stem 132a when in contact.
[0091] In some embodiments, a damper in the form of a spring 276
may be provided, as shown, to facilitate the lowering of the arm
256 against the bending instrument base 252. Likewise, the
detachable handles 270 which are attached to the bending instrument
base 252 at attachment knob 268 as well as the arm 256 at
attachment end 266 also help facilitate the lowering of the arm 256
against the base 252 to place the instrument 250 in a fully closed
position. Once the bending instrument 250 is in its fully closed
position with the flexible coupler 120 within the flexible coupler
mounting unit 254, the stem 132 is bent to the desired radius
chosen. FIG. 8G shows the bending instrument in the open position
with the arm 256 raised to allow the flexible coupler mounting unit
to swivel upwards. The flexible coupler 120 with the now bent stem
132b can be removed from the portal 266 by unscrewing it from the
flexible coupler mounting unit 254, as shown in FIG. 8G. FIG. 8H
shows the flexible coupler fully removed from the bending
instrument 250.
[0092] FIG. 9A illustrates one exemplary embodiment of a bone
fastener 160 for use with the modular spine stabilization system
100 of the present disclosure. The bone fastener 160 may comprise a
head portion 162 shaped like a tulip and a shank portion 166. The
head portion 162 may include a cavity 164 for receiving an
implantable device, and an enlarged head 184 of the shank portion
166 which may sit within the cavity 164. The diameter of the head
portion 162 may be in the range of about 5.5 to 9.5 mm. The shank
portion 166 may include an elongated shaft 168 extending from the
enlarged head 184 to a distal tip 172. The enlarged head 184 may
include a tool-engaging opening 186, as shown in FIG. 9D.
[0093] The shaft 168 of the shank portion 166 may be defined by a
first leading threaded portion 170a adjacent the distal tip 172, a
second trailing threaded portion 170c adjacent the head portion
162, and an intermediate threaded portion 170b extending between
the first and second threaded portions.
[0094] According to one aspect of the present disclosure, the first
leading threaded portion 170a can include quad lead threads, and
the second trailing threaded portion 170c can include quad lead
threads. Further, the shaft 168 may have the same nominal diameter
(i.e., outer thread diameter) throughout the entire length of the
shaft.
[0095] According to another aspect of the present disclosure, the
shank portion 166 has a generally uniform diameter from the second
trailing threaded portion 170c to the end of the intermediate
threaded portion 170b. The pitch of the intermediate threaded
portion 170b may be between about 4 and 5 mm. A conical part 180
may be provided in the transition between the second trailing
threaded portion 170c and the intermediate threaded portion 170b,
while the second trailing threaded portion 170c is generally
cylindrical. The intermediate threaded portion 170b may include
dual lead threads, in one embodiment.
[0096] The first leading threaded portion 170a may have a conical
shape in some embodiments. In some embodiments, the first leading
threaded portion 170a may include cutting notches 178, as shown in
FIG. 9A. The bone fastener 160 may be provided with cement holes
174 in some embodiments, as shown. Additionally, the bone fastener
160 may be color coded for different sizes, and may be configured
with a self-tapping distal tip 172.
[0097] As shown, a locking device 184 for securing the implantable
device within the cavity 164 may be provided. This locking device
184 may be a set screw, for example. The head portion 162 may be an
extended tulip head, to accommodate minimally invasive surgery
(MIS) instrumentation and techniques during implantation. FIG. 9B
shows a perspective view of the extended tulip head 192, which also
includes extended walls 194 forming the tulip head extension and
being attached at a scored or cutaway portion 196 that can be
broken off from the tulip head 162 after use.
[0098] FIG. 9C illustrates a detailed view of the shaft 166, while
FIG. 9D illustrates a top-down view of the shaft 168, both without
the attached tulip head portion 162.
[0099] Although the exemplary embodiment described and shown has a
first leading threaded portion 170a with quad lead threads, and a
second trailing threaded portion 170c with quad lead threads, it is
contemplated that other types of lead threads can also be utilized
such as dual lead threads, if so desired. For example, any of the
threaded portions 170a, 170b, 170c of the shank 166 may be provided
with double, triple or quad lead threads, although quad lead
threads will provide enhanced bone purchase.
[0100] FIGS. 10A and 10B illustrate an exemplary method of using
the bone fasteners 160 having the tulip head extension 192 attached
thereto with the modular spine stabilization system of the present
disclosure. FIG. 10A shows the bone fasteners 160 with attached
tulip head extensions 192 inserted into the patient's spine, while
FIG. 10B shows the system configuration or construct now placed
within the bone fasteners 160. These tulip head extensions 192 are
particularly helpful for MIS techniques. In addition, the tulip
head extensions 192 can be useful for performing rod reduction
procedures. Once the assembly of the stabilization system is
completed, and the subcomponents flexible couplers and rigid rods
are in their desired arrangement and secured with the bone
fasteners 160, the tulip head extensions 192 may be broken off at
the scored regions 196.
[0101] While the assembly of the present system is described as a
MIS technique, it is of course understood that the spine
stabilization system can be assembled with tradition open surgical
techniques as well. To facilitate this assembly in open surgery,
bone fasteners 160 may be provided having tulip head extensions but
of a shorter relative length than for those to be used in a MIS
technique.
[0102] Turning back to the instrument set 200, it is contemplated
that instruments such as a trocar awl, awl, screw dilator, dilator,
and screw length ruler may be provided. In addition, a tap, for
instance, with a 1/4 inch coupling, a tap with a dilator and
T-handle with a ratchet, a polyaxial screwdriver, for example,
having a straight handle and a T-handle alternative, and a nut
driver, for instance, with a 1/4 inch coupling, may also be
provided within this instrument set 200 as well.
[0103] In addition, FIGS. 11A to 11C show various views of an
exemplary embodiment of a flexible coupler and rod inserter tool
280 that may be part of the instrument set 200 of the present
disclosure. The inserter tool 280 may include an arm 282 extending
into a gripping end 284 for holding onto a flexible coupler and
rigid rod construct, a handle 286, and have a pivotable neck 288
connecting the arm 282 and handle 286, as shown in FIG. 11A, which
would allow the angular insertion of the implantable components of
the modular spine stabilization system 100. The pivotable neck 288
is angularly adjustable, and may be locked in position using a
tightening nut 312, for example, as shown in FIG. 11A in the
enlarged view. This inserter tool 280 may be especially helpful
when inserting by a MIS technique. The gripping end 284 may include
curved walls 292 that are configured to firmly grasp the flexible
coupler body 122, while finger projections 294 may be provided to
support and stabilize the elongated shaft 142 of the rigid rod 140
extending from the flexible coupler and rigid rod construct, as
shown in FIG. 11B. These finger projections 294 may be operatively
movable from an open position (FIG. 11B) into a closed position for
firmly gripping the flexible coupler body 122, as shown in FIG.
11C.
[0104] In the illustrated embodiment, the flexible coupler 120 is
threadedly connected to a rigid rod 140, and the construct is
grasped by the flexible coupler and rigid rod inserter tool 280. As
shown in FIG. 12A, incisions can be made to enable the inserter
tool 280 to access the spine 10. The upper-most incision lines
IL.sub.1 indicate the suggested length and location for the
incisions for enabling access of the inserter tool 280. The
incisions may be, for example, about 3 cm in length. The second set
of shorter incision lines IL.sub.2 (e.g., 1.5 cm) as shown below
upper-most incision lines IL.sub.1 are for the insertion of the
bone fasteners 160 at the adjacent levels.
[0105] FIGS. 12B to 12D illustrate a method of using the inserter
tool 280 to introduce the flexible coupler and rigid rod construct
into the patient, whereby the inserter tool 280 is able to hold the
flexible coupler and rigid rod construct while positioning it
between the walls 294 of the extended tulip extensions 292, and
seat the construct into the heads 162 of the bone screws 160. The
angled and adjustable neck 288 of the inserter tool 280 enables the
user to have the necessary angle of approach to perform the steps
in a minimally invasive manner.
[0106] The modular spine stabilization system 100 of the present
disclosure may be used for stabilization of both sides of a
patient's spine, as illustrated in FIG. 13 in which a series of
flexible coupler to rigid rod constructs may be assembled for
implantation along both sides of the spine. In such a case, a
crosslink 300 may be used to further stabilize the system 100.
Accordingly, a measurement tool may be provided with the instrument
set 200 to determine the appropriate length of the crosslink 310 to
use.
[0107] An exemplary embodiment of a measurement tool 290 is shown
in FIG. 14A. The measurement tool 290 may include a pair of
pivoting arms 292 hinged together in a manner similar to scissors
or pliers, with one end of the pivoting arms 292 interconnected and
cooperating to indicate measurement size. As shown, one of the
pivoting arms 292 may include a laterally extending bar 300 having
indicia 302 representing units of length thereon, while the other
pivoting arm 292 may have a slot 304 for slidingly receiving the
laterally extending bar 300. This same pivoting arm 292 may further
include a window 306 through which the user may view the indicia
302 on the laterally extending bar 300 as it slides across the slot
304. A locking nut 308 may be provided to lock the laterally
extending bar 300 within the slot 304 and prevent further movement
of the pivoting arms 292.
[0108] At the opposite end of the pivoting arms 292 are tips 296
configured to be placed on the elongated shafts 142 of laterally
opposed rigid rods 140 for measuring the distance between the rigid
rods 140 located on opposed sides of the spine, as shown in FIG.
14B. For instance, as shown in FIG. 14A, the tips 296 may have a
curved inner surface for placement against the cylindrical surface
of the elongate shafts 142, similar to the manner shown in FIG.
14B. This measured distance can then determine what length
crosslink 310 would be suited for use at this level.
[0109] In another embodiment, the tips 296 may be configured for
placement within the set screws 184 inside the head portions 162 of
bone screws 160, in order to measure the length between the bone
screws 160, as shown in FIG. 15B. As shown in FIG. 15A, the tips
296 may be shaped and sized to seat within the set screws 184. When
used in this manner, the measurement tool 290 can also serve to
determine the length of a construct, or between bone screws 160, on
the same side of the spine.
[0110] While FIG. 13 shows an embodiment in which the pair of
constructs is essentially mirror images of one another, it is also
understood that there can be variances between one of the
constructs of the pair. For example, it is possible that one could
use a coupler at one level, on one side, and then a rod at the same
level, on the opposite side, of the spine.
[0111] Other embodiments will be apparent to those skilled in the
art from consideration of the specification and practice of the
embodiment disclosed herein. It is intended that the specification
and examples be considered as exemplary only, with a true scope and
spirit of the embodiment being indicated by the following
claims.
* * * * *